Description

Istio is an open platform to connect, manage, and secure microservices. Prior to 1.29.1, 1.28.5, and 1.27.8, a vulnerability in Envoy RBAC header matching could allow authorization policy bypass when policies rely on HTTP headers that may contain multiple values. An attacker could craft requests with multiple header values in a way that causes Envoy to evaluate the header differently than intended, potentially bypassing authorization checks. This may allow unauthorized requests to reach protected services when policies depend on such header-based matching conditions. This vulnerability is fixed in 1.29.1, 1.28.5, and 1.27.8.

INFO

Published Date :

2026-03-10T21:58:53.354Z

Last Modified :

2026-04-07T02:39:59.774Z

Source :

GitHub_M
AFFECTED PRODUCTS

The following products are affected by CVE-2026-31838 vulnerability.

Vendors Products
Istio
  • Istio
REFERENCES

Here, you will find a curated list of external links that provide in-depth information to CVE-2026-31838.

URL Resource
https://github.com/istio/istio/commit/004fd6921314a8e2293fd195d91645dcbbff0aa1 cve-icon cve-icon
https://github.com/istio/istio/security/advisories/GHSA-974c-2wxh-g4ww cve-icon cve-icon cve-icon
https://nvd.nist.gov/vuln/detail/CVE-2026-31838 cve-icon
https://www.cve.org/CVERecord?id=CVE-2026-31838 cve-icon
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CVSS Vulnerability Scoring System

Detailed values of each vector for above chart.
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Detailed values of each vector for above chart.
Attack Vector
Attack Complexity
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User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact